Electric condenser



. Nov. 22, 1938. M. OSNOS ELECTRIC CONDENSER ori inal Filed May 5, 1932INVENTOR MENDEL OSNOS ATTORNEY Patented Nov. 22, 1938 UNITED STATESELECTRIC CONDENSER Mendel Osnos, Berlin, Germany, assignor to Telciunken Gesellschaft fiir Drahtlose Telegraphi m. b. H.,Berlin, Germany,a corporation of Germany Original application May 5, 11932, Serial No.

Divided and this application February 24, 1936, Serial No. 65,228

2 Claims.

This invention relates to an improved electric condenser whose capacityvaries very markedly with the temperature. A condenser of this inventionis particularly adapted to use in a cir- 5 cult for tuning the capacityof a vacuum tube transmitter, especially when short waves are employed,and is to be controlled from a remote point or else'for the purposes ofstabilizing frequency of a valve transmitter controlled by the agency ofa piezo-electric crystal.

This applicationis a division of my copendl'ng application Serial No.609,401, filed May 5, 1-932. According to the invention a condenser ofthis iiindis created so that its active surface or its inter-electrodedistance, or else both, are adjusted or regulated by a fluid possessinga large temperature coefilcient of expansion or else by a gas (say, air)or a combination thereof. It is then feasible to heat the liquid or thegas or a combination of both, for example, by means of electric heatingto a more or less high degree, with the result that the capacity of thecondenser is regulable or adjustable at will at any desired rate. -,Asimple embodiment of this invention is shown by the single figure of thedrawing, in which 3 is a glass jar or bottle having a base or bottomconsiderably larger in area than the cross-section of the neck. Thespace within the jar 3 is filled with a suitable liquid, for example,mercury 2. A metallic electrode 2| is located at the neck of jar; andcan be screwed in or out by means of a screw thread 4, fastened on acollar ring or flange 22 so as to be at the correct distance above theliquid level,

' When the temperature of the liquid mercury increases, its level willrise and decrease the space between electrode 2| and mercury 2, thuschangportion to the variation in temperature. For example, if the liquidmercury is heated by means of the heater winding, 1, which is woundwithin a coil form 9, preferably of metal, the coil 7 being connected toan external source of 'electric current (not shown) by means of leads 6,the liquid 2 will be caused to expand, the distance between its surfaceand the electrode 2| decreases and the capacity of the condenserincreases.

I claim:

, 1. An electric condenser comprising an insulating bottle-likecontainer having a base of substantially larger area than the crosssection of the neck of said bottle, a conducting fluid within saidcontainer, an electrode closing the opening of said container, andfmeansfor changing the,

capacity between said conducting liquid and said metallic electrode.

2. An electric condenser comprising an insulating bottle-like containerhaving a base of substantially larger area than the cross section of theneck of said bottle, a conducting fluid within said container, anelectrode closing the opening of said container, and electrical heatingmeans at the base of said container for controlling the ing the capacityof the condenser in direct procapacity between said conducting liquidand said i metallic electrode.

- I MZENDEL OSNOS.

